Notch worn in brake pad ledge

[abebehrmann]

I've noticed every once in a while my right front caliper will start to stick. I pulled everything apart and noticed this little notch worn into the bottom brake pad ledge(see pic). I'm wondering what might cause this and what can I do to fix it? I believe I remember reading someone dealing with this (I think it was msmoorenburg?) and he fixed it by filling the notch by welding and grinding it down flush. Is this the only way to fix this besides replacing the whole thing? I'm saving up for a welder but am still short on funds. I was thinking maybe a dab of jbweld fully cured and filed flush would do the job but I'm not sure if this would be my best option. Any information you guys could give me would be greatly appreciated.